High temperature scrap cleaning conveyor

ABSTRACT

A high temperature scrap cleaning conveyor includes a conveyor comprised of a conveying deck, a mechanism for oscillating the deck, and a water-filled pan beneath the deck. Shredded scrap metal contaminated primarily with paint, oil and grease is deposited on one end of the conveying deck and the oscillating motion of the deck causes the scrap to move toward the deck&#39;&#39;s opposite end, tumbling and turning as it does. Water is circulated through the pan and this water not only insulates the oscillating mechanism from the heated conveying deck, but it also cools the conveying deck, since the oscillations cause the water to splash against the underside of the deck. A framework supports an insulated closure which extends over and along the sides of the conveying deck, and this closure defines a fire chamber in which a series of transversely extending burners are located. The burners produce downwardly directed flames which not only raise the temperature of air within the fire chamber, but also impinge on the scrap carried on the conveying deck and burn the contaminants from the scrap. Since the scrap tumbles as it advances, all surfaces thereof are presented toward the flame. An airstream is created within the fire chamber by a fan, and the air for this airstream is derived from air gaps existing between the sides of the conveying deck and side curtains which form the sides of the insulated closure. These side curtains may be adjusted inwardly and outwardly to control the size of the air gaps and this in turn controls the air velocity through the fire chamber. The curtains may be removed altogether to gain access to the burners and conveying deck. At the discharge end of the oscillating conveyor the airstream enters a smoke elimination tower having a high velocity burner at its entrance for raising the temperature of the airstream sufficiently to consume smoke, fumes, and most entrained material. The smoke elimination tower is connected with a cooling chamber where a high pressure water mist is sprayed into the airstream for cooling the airstream and for removing the larger particulates therefrom. Downstream from the cooling chamber, the airstream flows through a plate-type impingement scrubber where more particulates are removed, and thence into a cyclone collector where the airstream loses velocity and the remaining particulates drop out. The drain water from the cooling chamber and scrubber flows into the cyclone collector where it flushes the particulates dropped therein. The water discharges from the collector into a settling tank for clarification and is recycled by a pump through the water pan of the oscillating conveyor. Only fresh water is supplied to the nozzles of the cooling chamber and to the scrubber. The fan is located downstream from the cyclone colector and discharges the airstream into the atmosphere in a purified condition. The foregoing units are interlocked and no one unit is operated independently.

United States aterit [1 1 Torrence 1 Oct. 2, 1973 1 HIGH TEMPERATURESCRAP CLEANING CONVEYOR [75] Inventor: James L. Torrence, Port Richey,

V Fla. [73 Assignee: American Pulverizer Company, St.

Louis, Mo. 22 Filed: Dec. 16, 1971 [21] Appl. No.: 208,685

' [52] U.S. Cl 432/72, 432/266, 198/218, 34/185,110/18 R [51] Int. Cl.865g 21/00 [58] Field of Search 263/21, 6; 34/242,

[56] References Cited Primary Examiner-John .1. Camby AssistantExaminer-Henry C. Yuen AttorneyEdward A. Boeschenstein et a1.

[57] ABSTRACT A high temperature scrap cleaning conveyor includes aconveyor comprised of a conveying deck, a mechanism for oscillating thedeck, and a water-filled pan beneath the deck. Shredded scrap metalcontaminated primarily with paint, oil and grease is deposited on oneend of the conveying deck and the oscillating motion of the deck causesthe scrap to move toward the decks opposite end, tumbling and turning asit does. Water is circulated through the pan and this water not onlyinsulates the oscillating mechanism from the heated conveying deck, butit also cools the conveying deck, since the oscillations cause the waterto splash against the underside of the deck. A framework supports aninsulated closure which extends over and along the sides of theconveying deck, and this closure defines a fire chamber in which aseries of transversely extending burners are located. The burnersproduce downwardly directed flames which not only raise the temperatureof air within the fire chamber, but also impinge on the scrap carried onthe conveying deck and burn the contaminants from the scrap. Since thescrap tumbles as it advances, all surfaces thereof are presented towardthe flame. An airstream is created within the fire chamber by a fan, andthe air for this airstream is derived from air gaps existing between thesides of the conveying deck and side curtains which form the sides ofthe insulated closure. These side curtains may be adjusted inwardly andoutwardly to control the size of the air gaps and this in turn controlsthe air velocity through the fire chamber. The curtains may be removedaltogether to gain access to the burners and conveying deck. At thedischarge end of the oscillating conveyor the airstream enters a smokeelimination tower having a high velocity burner at its entrance forraising the temperature of the airstream sufficiently to consume smoke,fumes, and most entrained material. The smoke elimination tower isconnected with a cooling chamber where a high pressure water mist issprayed into the airstream for'cooling the airstream and for removingthe larger particulates therefrom. Downstream from the cooling chamber,the airstream flows through a p1ate-type impingement scrubber where moreparticulates are removed, and thence into a cyclone collector where theairstream loses velocity and the remaining particulates drop out. Thedrain water from the cooling chamber and scrubber flows into the cyclonecollector where it flushes the particulates dropped therein. The waterdischarges from the collector into a settling tank for clarification andis recycled by a pump through the water pan of the oscillating conveyor.Only fresh water is supplied to the nozzles of the cooling chamber andto the scrubber. The fan is located downstream from the cyclone colectorand discharges the airstream into the atmosphere in a purifiedcondition. The foregoing units are interlocked and no one unit isoperated independently.

12 Claims, 8 Drawing Figures United States Patent 1 [111 3,762,858Torrence Oct. 2, 1973 PATENTED UET- 2 I973 sum 10F 3 xmm Mu; MI l lmPATENTED BET 2l975 SHEET 38F 3 FIG,3

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HIGH TEMPERATURE SCRAP CLEANING CONVEYOR BACKGROUND OF THE INVENTIONThis invention relates in general to an apparatus and process forcleaning shredded metal and, more particularly, to a high temperaturecleaning conveyor and process.

Large quantities of scrap still are consumed in the steel industry forconversion into basic steel products, and this scrap steel is to a largemeasure purchased from independent scrap dealers. In order to avoidcontamination and a resulting inferior grade of steel, the scrap steelutilized in current steel making processes must be relatively clean.Consequently, steel mills prefer and indeed pay a premium price forscrap which is physically clean, that is, scrap which is free from andnot intermixed with non-ferrous metal impurities and non-metallicparticles, and is also free of grease, oil and paint.

Junked automobiles provide one of the largest sources of scrap steel andsimilarly discarded appliances such as stoves, refrigerators, hot waterheaters and the like and constitute a significant source. The steel inthese products usually possess a coating of paint and furthermore isoften covered with grease and oil. Moreover, these products contain asignificant amount of non-metallic substances such as glass, plastic,rubber, and upholstery material, and limited quantities of non-ferrousmetals are also present, usually in the form of small electrical wiresand aluminum. Consequently, junked automobiles without additionalprocessing are of little value to the basic steel industry.

Heretofore junked automobiles and appliances have been stripped ofvaluable non-ferrous metals and glass and the remaining hulks have beenburned in open fires to free the steel in those hulks of paint, grease,oil and those non-metallic substances which will burn. Thereafter, therelatively clean hulks were shredded and the shredded steel scrap soldto steel mills. This procedure was time consuming and required muchmanual labor. Furthermore, it left many contaminants with the steel. Inany event, the foregoing process is no longer available, for the Federalgovernment has prohibited burning automobile bodies in open firesbecause of the severe air pollution created by such burning.

Currently, junked automobiles and appliances are shredded and thereduced material is run through a magnetic separator to separate thesteel therefrom. The steel so separated is then passed through largerotortype kilns or incinerators which are connected with coolingequipment, smoke incinerators and other antipollution devices. Equipmentof the foregoing nature is exceedingly large in size, extremely complexand expensive, and requires extensive foundation work. It furthermoreconsumes large amounts of electrical energy and requires constantmaintenance, which due to its complex nature can only be conducted byhighly skilled personnel. Accordingly, equipment of the foregoing naturerequires large plant facilities and is well beyond the financialcapabilities of all but the largest dealers in scrap. Clearly, suchequipment cannot be operated at a profit where the plant output rangesbetween to tons per hour.

SUMMARY OF THE INVENTION One of the principal objects of the presentinvention is to provide an apparatus and process for burning oil,grease, paint and the like from shredded steel scrap. Another object isto provide an apparatus and process of the type stated which reducesupholstery material, sound deadening material, small particles of copperwires, insulation and the like which may adhere to or be intermixed withthe steel scrap to vapor or ashes. A further object is to provide anapparatus of the type stated which is highly compact and does notrequire large plant facilities or extensive foundation work. Anotherobject is to provide an apparatus of the type stated which can be usedin existing scrap processing yards without extensive remodeling orrearrangement of equipment. An additional object is to provide anapparatus of the type stated which is simple in construction and doesnot require much maintenance. Still another object is to provide aprocess and apparatus of the type stated which requires a minimal amountof energy. Yet another object is to provide a process and an apparatuswhich will make it economically possible for small and moderately sizeddealers in scrap to process steel scrap for sale to steel mills. Theseand other objects and advantages will become apparent hereinafter.

The present invention is embodied in a high temperature scrap cleaningapparatus including a conveyor for tumbling the scrap while contaminantsare burned from it. The invention also includes fan means for creatingan airstream over the scrap and antipollution means for cleansing theairstream before it is discharged into the atmosphere. The inventionalso consists in the parts and in the arrangements and combinations ofparts hereinafter described and claimed.

DESCRIPTION OF THE DRAWINGS In the accompanying drawings which form partof the specification and wherein like numerals and letters refer to likeparts whenever they occur:

FIG. I is a side elevational view of a high temperature scrap cleaningconveyor constructed in accordance with and embodying the presentinvention;

FIGS. 2, 3 and 4 are sectional views taken along lines 22, 3-3 and 4-4respectively of FIG. I;

FIG. 5 is an enlarged sectional view of an expansiontype bracket forsecuring the agitating scrap conveying deck to its supporting frame;

FIG. 6 is a fragmentary sectional view showing the water inlet to thepan of the oscillating conveyor;

FIG. 7 is a fragmentary sectional view showing the water outlet on thepan of the oscillating conveyor; and

FIG. 8 is a sectional view showing a thermocouple attached to theunderside of the conveying deck of the oscillating conveyor forcontrolling the temperature in the fire chamber above the deck.

DETAILED DESCRIPTION Referring now in detail to the drawings, 2designates a high temperature scrap cleaningconveyor which at one endreceives shredded steel scrap from a product feed conveyor 4 (FIG. l)and at its opposite end discharges the shredded scrap in a physicallyclean condition onto a product removal conveyor 6. The scrap deliveredto the cleaning conveyor 2 by the feed conveyor 4 is derived from oldautomobile hulks, home appliances, and the like which, after a minimalamount of stripping to remove valuable products and metal therefrom,have been shredded to reduce them to a more compact form. The shreddedmaterial is then run through a magnetic separator to separate the steeland non-ferrous particles. Despite the magnetic separation, non-metallicsubstances such as upholstery, sound deadening material, smallelectrical wires, insulation, adhere to or remain embedded in theshredded steel. Moreover, much of the shredded steel has at least somepaint adhering to it as well as a heavy coating of grease and oil.

The high temperature conveyor 2 contains an oscillating conveyor whichconstitutes the assembly for transporting shredded scrap from the feedconveyor 4 to the removal conveyor 6 and for supporting that scrap whileit is cleaned. The oscillating conveyor 10 includes (FIGS. 1 and 2) afixed base 12 which is set upon the ground and has a pair oflongitudinal members 14 to which the lower ends of upstanding supportbars 16 are connected such that they pivot or swing relative to themembers 14 about axes perpendicular to the members 14. At their upperends the support bars 16 are connected to an oscillating frame 18 suchthat they pivot in a like manner relative to that frame. The bars 16 arefurthermore disposed obliquely to the base 12 and frame 18 and extendrearwardly from the former to the latter. The frame 18 at its sides hasa pair of longitudinal channel members 20 and welded to the uppermostflanges on the channel members 20 is a water pan 22 which bridges themembers 20 and is depressed considerably between them. The water pan 22further- 'more has lateral extensions 24 which project horizontallybeyond the sides of the members 20 at both ends of its depressed portionto retain a pool of water therein.

In addition to the pivotally connected support bars 16 the oscillatingframe 18 is further supported by a series of coil springs 26 whichlikewise extend between the base 12 and the supported frame 18 and abutagainst angled spring seats 28 on the base 12 and frame 18. The springs26 are oriented with their axes generally perpendicular to the supportbars 16. At the infeed end of the oscillating conveyor 2, the fixed base12 supports a variable speed drive motor 30 (FIG. 1) which rotates aconveyor drive shaft 32 journaled in pillow blocks 34 on the base 12.Fixed to the drive shaft 32 are a pair of eccentrics 36 which areconfined in the ends connecting rods 38 such that they rotated relativeto the connecting rods 38 and impart a longitudinal shifting movement ofan oscillatory nature thereto. The opposite ends of the connecting rods38 are also attached to the oscillating frame 18 so that the oscillatorymovement is also imparted to the frame 18. The oscillating frame 18carries a conveying deck 40 (FIG. 2) which bridges the depressed portionof the water pan 22 and has upwardly and outwardly turned containingwalls 42 along its sides. The containing walls 42 are disposed directlyabove the lateral extensions 24 of the pan 22 and at spaced intervalsare provided with supporting brackets 44 (FIG. 5) having horizontalflanges 45 at their lower ends. These flanges 45 have slots 46 whichextend perpendicular to the longitudinal axes of the conveying deck 40.The slots 46 receive bolts 47 which further extend through the lateralextensions 24 of the pan 22 and secure the conveying deck 40 to theframe 18. interposed between the lateral extensions 24 and the overlyingflanges 46 are asbestos slip pads 48, through which the bolts 47 extendalso. Since the slots 46 are elongated transversely of the conveyingdeck 40, they permit the conveying deck 40 to expand laterally of thewater pan 22 and frame 18 with out buckling. Thus, the conveying deck 40will retain its proper configuration even when its temperature isconsiderably higher than the temperature of the pan 22 and the frame 18.The conveying deck 40 extends beyond the terminal end of the frame 18,and this longitudinal projection of the deck 40 is disposed above theend of the product removal conveyor 6.

When the conveyor drive motor 30 is energized the frame 18 willexperience an oscillating movement and this movement wll be transmittedto the conveying deck 40. Consequently, shredded scrap on the deck 40will agitate in the vertical direction and will be advanced toward theremoval conveyor 6. Since the movement is effected by verticalagitation, the scrap will tend to tumble or otherwise turn and changeposition on the deck 40 as it is advanced.

At its one end the water pan 22 is provided with an inlet pipe (FIG. 6)49 which projects outwardly from the depressed portion thereof andextends through the adjacent channel member 20 of the frame 18. Beyondthe channel member 20, the pipe 49 turns upwardly and terminates at anupwardly opening funnel 50. At its opposite end, the water pan 22 isprovided with an outlet pipe Sl (FIG. 7) which also projects from thedepressed portion thereof through the adjacent channel member 20. Theouter end of the pipe 51 is fitted with a swivel connector 52 to whichan elbow 53 is connected, and the elbow 53 carries a short pipe nippleS4. The angular disposition of the elbow 53 determines the height of thefree end of the nipple 54, and that height is the same as the waterlevel in the pan 22. Thus, the elbow 53 controls the level of the waterin the pan 22. The pipe nipple 54 is located over a funnel 55 on the endof a drain pipe 55a leading to a sewer.

The oscillating conveyor 10 extends through a tunnel-like framework 56(FlGS. 1 and 2) which carries a thick overlying insulation blanket 58and a series side curtain 60. The insulation blanket 58 extendscompletely across the top of the oscillating conveyor 10 and theframework 56 as well, and has a metallic cladding. The side curtains 60(FIG. 2) also carry heat insulative material and depend downwardly fromthe insulation blanket 60, extending completely across the sides of theconveying deck 40. Thus, the blanket S8 and ourtains 60 in combinationform an insulated closure over the conveying deck 40, and this insulatedclosure defines a fire chamber 61, the base of which is the conveyingdeck 40.

Each side curtain 60 at its upper end has a series of inwardly turnedflanges (FIG. 2) which have downwardly turned inner lips 64. Thetunnel-like framework 56 on the other hand carries downwardly extendingsupporting brackets 66 which, generally speaking, are located directlyabove the upper edges of the confining walls 42 on the conveying deck40. The brackets 64 have upwardly opening channels 68 at their lowerends, and these channels 66 receive the downwardly turned inner lips 64of the flanges 62 on the curtains 60 so that the curtains 60 aresuspended from the brackets 64. The channels 68 are considerably widerthan the downwardly turned lips 64 so that the curtains 60 may beshifted inwardly and outwardly. This, in turn, permits adjustment of theair gap between the inner face of each side curtain 60 and the upperedge of the containing wall 42 located opposite to that curtain 60.

The flanges 62 may be disengaged from the brackets 66 by lifting theside curtains 60 upwardly and then pulling them outwardly so that thelips 64 of the flanges 62 pass beyond the channels 68 of the brackets66. Thereupon, the curtains 60 may be lowered to gain access to theconveying surface of the conveying deck 40. This enables the operator toremove or dislodge oversize objects which impede movement of the scrapalong the oscillating conveying deck 40. in order to support the sidecurtains 60 while they are removed from their normal positions,temporary support brackets 70 are attached to the sides of the framework56. Also, to facilitate removal and replacement of the side curtains 60,they are provided with handles 72.

Above the feed end of the oscillating conveyor the framework 56 supportsa feed chute 76 (FIG. 1) which is disposed below the discharge end ofthe feed convcyor 4. The feed chute 76 channels the scrap discharged bythe feed conveyor 4 onto the conveying deck 40 of the oscillatingconveyor 10.

The tunnel-like framework 56 further supports a series of burners 80(FIG. 2), and these burners are housed within the insulated fire chamber61 formed by the insulation blanket 58 and the side curtains 60. Inparticular, each burner 80 is supported at its ends from the framework56 so that it is disposed above the conveying deck 40 and scrap thereon,and is oriented such that it extends transversely across the conveyingdeck 40. Spaced longitudinally along each burner 80 are flame orifices82 which open downwardly, that is toward the conveyor deck 40. Eachburner 80 at its center is connected to a header 84 which extendsupwardly through the insulation blanket 58 and then turns laterallytoward one side of the framework 56. The header 84 terminates at anaspirator 86 and projecting into the aspirator 86 is a gas supply pipe88 having a shutoff cock 90 therein. Beyond the shutoff cocks 90 thesupply pipes 88 of the several burners MD are connected to a common gassupply line 92 which leads to a gas main 93 containing a combustiblegas. Prior to the supply pipe 88 leading to the first burner 80, the gassupply line 92 has a line pressure safety valve 94, a gas pilot safetyvalve 96 provided with a manual reset, a modulating valve 97, and a linepressure regulator 98. The modulating valve 97 is connected to andoperated by a thermocouple 99 (FIG. 8) which is housed within athermocouple well 99a attached to the underside of the conveying deck40.

Combustible gas from the supply line 92 enters the supply pipes 88 fromwhich it is injected into the headers 84 at the aspirators 86 therein.The gas flowing into the headers 84 causes air to be drawn into theheaders 84 at the aspirators 86 also and in sufficient quantities tosupport combustion of the gas. The air and gas are thoroughly mixed bythe time they reach the burners 8t) and this combustible mixtureissuesfrom orifices 82 in the burners 80 as high velocity jets. Whenignited these jets produce downwardly directed flames which impinge uponthe scrap supported by the conveying deck 40. Additional air is suppliedto the fire chamber 61 through the air gaps existing between thecontaining walls 42 on the conveyor deck 40 and the inside faces of theside curtains 60. If this does not support combustion, thermocouplesbuilt into the burners 80 will shut off the gas supply.

As will be described in greater detail, a fan creates an airstreamwithin the fire chamber 61 and the air for this airstream is derivedprimarily from the air gaps between the conveyor decks 40 and the sidecurtains 60. Since the side curtain 60 may be moved inwardly andoutwardly, the size of the air gaps and the quantity of air drawnthrough them may be adjusted.

At the terminal end of the oscillating conveyor 10, that is at the endwhich discharges onto the removal conveyor 6, the tunnel-like framework56 carries an air cleansing stack 100 (FIG. 4) which defines a smokeelimination chamber 102 in which the airstream also exists. Within thelower end of the chamber 102 the stack W0 supports a high velocity andhigh pressure burner 104 which is connected to the gas main 93 through asupply line 106 having a line pressure safety valve 108 in it.Combustion air for the burner 104 is derived from a centrifugal blower110 mounted on the exterior of the stack 100 and connected to the burner104 through an air duct 112 (FIG. 1). The burner 104i heats theairstream as it passes from the tire chamber 61 into the smokeelimination chamber 162 and this heating removes smoke from theairstream. Thus, the burner 104 and smoke elimination chamber 102constitute a smoke incinerator.

At its upper end the cleaning stack 100 has a lateral offset 114 whichdefines a cooling chamber 116 (FIG. 4) located immediately beyond thesmoke elimination chamber 102. The lower ends of the chambers 102 and116 are separated from one another by a partition member 118 containedwithin the stack 100, but the upper ends of the two chambers 102 and 116open into each other so that the airstream upon leaving the smokeelimination chamber 102 enters the cooling chamber 116. Within thecooling chamber 116, the offset portion 114 of the stack 100 mountsseveral baffle plates 120, 122 and 124 which are arranged to create asepentine path through the cooling chamber 116. In particular, thebaffle plate extends obliquely downwardly from the upper end of thepartition member 118, while the baffle plate 122 is disposed beyond thelower free end of the plate 120 and is generally perpendicular thereto.The baffle plate 124, on the other hand, extends obliquely upwardly fromthe lower edge of the plate 122 and is parallel to the plate 120., butis spaced downwardly therefrom. At the trough-like juncture of theplates 122 and 124, a drain tube 125 is provided so that water andparticulates do not collect in that trough-like juncture. Near the upperoutside corner of the cooling chamber 116, nozzles 126 are mounted onthe offset portion 114 of the stack 100, and these nozzles 126 are setto direct a spray of fresh water onto the upwardly presented surfaces ofall of the oblique baffle plates 120, 122, and 124. The water sprayedfrom the nozzles 126 is in the form of a high pressure mist. That mistcools the airstream passing through the cooling chamber 116 and furtherremoves minute particulates from the airstream. It also moistens thebaffle plates 120, 122 and 124 so that the particulates in the airstreamadhere to these moistened plates as the airstream blows against them.

Attached to the bottom of the lateral offset portion 114 is a slot-typeair scrubber 130 (FIGS. 3 and 4) through which the airstream passesafter leaving the cooling chamber 116. The scrubber 130 is conventionalin construction and can be purchased as a unit. it contains wet platesand counterflow water sprays. The impingement of the airstream on thewet plates and its passage through the counterflow sprays removespractically all of the remaining particulates entrained in theairstream.

Both the nozzles 126 and the air scrubber 130 are supplied with waterfrom a water line 132 which is connected to a high pressure supply offresh water.

The discharge end of the air scrubber 130 is connected to a duct 137which directs both the airstream and water discharged from the scrubber130 to a cyclone-type collector 136 (HO. 3). In particular, thecollector 136 is closed and includes a cylindrical side wall 138 and aconical bottom wall 140. The duct 137 connects tangentially with theside of the cylindrical side wall 138 and is oriented such that theairstream discharged therefrom initially flows tangentially with respectto the inside surface of the side wall 138. The enlarged volume of thecollector 136 causes the airstream to lose velocity, and this coupledwith the cyclonic flow causes the remaining entrained particulates todrop out and further drop from the air and fall onto the conical bottomwall 140. The conical bottom wall 140 has a downwardly extendingdischarge tube 142 connected to the center or lowermost portion thereof.Accordingly, the particulates lost in the cyclone collector .136 areflushed into the discharge tube 142.

The discharge tube 142 leading from the lower end of thecyclonecollector 136 extends into and terminates within a settling tank 146(FIG. 3), and a water pump 147 is connected with the tank 146 through astand pipe l48which terminates close to the upper surface of the waterin the tank 146. Before the water enters the pump 147, it passes througha filter to remove any particulates therefrom. The discharge port of thepump 147 is connected to a supply line 150 which leads to the funnel 50on the inlet pipe 49 for the water pan 22, so the water in the pan 22 isderived from the tank Finally, the upper end of the cyclone collector136 is connected to a duet 154 (FIG. 1) which leads to a fan 156. Thefan 156 in turn discharges into the atmosphere througha discharge stack158. The fan 156 creates the airstream previously discussed.

OPERATlON Prior to introducing scrap into the high temperature cleaningconveyor 2 for removal of contaminants therefrom, the fan 156 isenergized and this creates an airstream which traced backwardly from thefan 156 flows through the duct 154, the cyclone collector 136, the duct147, the air scrubber 130, the cooling chamher 116, the smokeelimination chamber 102 and the fire chamber 61. lndeed, the airstreamgenerated by fan 156 creates an air flow along the upper surface of theconveying deck 40 for the oscillating conveyor 10,.

. that is within the fire chamber 61, and that air flow is the samedirection as the conveyor advances this scrap.

Once the airstreamalong the upper surface of the conveying deck 40 isinitiated, the valve 94 is opened to allow combustible gas from the gasmain 93 to flow through the gas supply line 92. This gas enters thesupply pipes 88, and as it is injected into the headers 84 it draws airthrough the aspirators 86 so that the gas flowing through the headers 84is mixed with air. This mixture of gas and air flows into the burners 80and is discharged therefrom through the orifices 82 as relatively highvelocity jets. These jets are ignited by a pilot flame or any otherconventional burner lighting device and are consequently converted intoflames which extend downwardly and impinge on the upper surface of theconveying deck 40. Should the aspirators 86 fail to supply sufficientair to support combustion of the combustible gas introduced into theheaders 84, additional air is supplied by the air flow passing along theconveying deck 40, and that additional air is derived from the air gapsexisting between the sides of the conveying deck 40 and the side curtain60. Since the side curtains 60 are movable inwardly and outwardly, thesize of those air gaps and the amount of air derived from them may becontrolled. In any event, sufficient air exists to support combustion ofthe combustible gas within the fire chamber 61, and this combustion isregulated at the valve 94 or by the modulating valve 97 to maintain thetemperature in the fire chamber 61 at between 600F. and 900F.

In addition, the centrifugal blower is energized and the gas valve 108is opened so as to supply combustion air and combustible gas to the highvelocity and high pressure burner 104 located in the base of aircleaning stack 100. This elevates the temperature of the airstreamflowing through the chamber 102.

Also, the water pump 147 is energized and that pump draws water from thesettling tank 146 and discharges it into the water pan 22 through thefunnel 50 and inlet pipe 49. By rotating the elbow 53, the level of thewater in the pan 22 is adjusted, and that level is such that when theframe 18 of the conveyor 10 oscillates, the water from the pan 22 willsplash against the underside of the conveyor deck 40. Thus, the waterpan 22 serves two purposes. First, it cools the conveyor deck 40 andprevents it from warping under the intense heat from the burners 84, andsecond it insulates the frame 18 and lower portions of the conveyor 10from the heat of the fire chamber 61.

The high pressure water in the line 132, which is fresh water, isdischarged therefrom through the nozzle 126 and the slot-type airscrubber 130. This water leaves the nozzles 126 as a high pressure mistwhich passes through the high temperature airstream in the coolingchamber 116 and cools and cleans the same. The spray also impingesagainst the baffles 120, 122 and 124 enabling particulates to adherethereto, and thereafter leaves the cooling chamber 116 by way of thedrain tube 125 which discharges into the air scrubber 130. The watersupplied to the air scrubber is converted into a counterflow sprays andfurther moistens plates therein. in any event, the water dischargedthrough the nozzles 126 and into the scrubber 130 eventually cascadesthrough the duct 137 and into the cyclone collector 136 where it flowsacross the conical bottom wall 140 thereof and enters the settling tank146 for introduction into the water pan 22.

Once the temperature within the fire chamber 61 above the oscillatingconveyor 10 reaches the desired valves, which is usually between 600Fand 900F, the product fed conveyor 4, the oscillating conveyor 10, andthe removal conveyor 6 should all be energized if they are not alreadyin operation. Shredded steel scrap is then allowed to flow along thefeed conveyor 4 toward the feed chute 76 of the high temperatureconveyor 2. This scrap constitutes steel shreddings which may be derivedfrom shredded automobile hulks, home appliances, and the like. Much ofit possesses a coating of paint, and may further be covered withupholstery fibers, grease and oil. Before being introduced into the feedconveyor 4 the shredded scrap should be run through a magnetic separatorto eliminate non-ferrous metals and other non-ferrous substancestherefrom. Notwithstanding the magnetic separation, the scrap may havenon-ferrous metals such as small copper wires or aluminum embedded init, and the same is true of other non-ferrous substances such as sounddeaden ing material, plastic, glass and the like. Also the paint andgrease and oil remain adhered to the scrap. Thus, the shredded scrap onthe feed conveyor 43 is not physically clean from a metallurgicalstandpoint and will not be accepted by steel mills for conversion intobasic steel products.

The feed conveyor 4 discharges the contaminated scrap into the feedchute 76 (FIG. 1) of the high temperature cleaning conveyor 2, and thefeed chute 76 directs the scrap onto the feed end of the oscillatingconveyor 10, or more particularly onto the conveying deck 40. Thesprings 26 and support bars 16 which carry the frame 18 on which theconveying deck 40 is mounted and the eccentric 36 and connecting rods 38are all arranged such that the oscillatory motion imparted to theconveying deck 40 advances the scrap along the conveying deck 40 towardthe cleaning stack 100 and removal conveyor 6. Moreover, the oscillatorymovement of the deck 40 tends to roll or tumble the individual pieces ofscrap so that the surfaces of the individual pieces are constantlychanging position and never face in any one direction for an extendedperiod of time.

As the shredded scrap tumbles beneath the burners 80, the high velocityflames issuing therefrom impinge against that scrap (FIG. 2) and burnoil, grease, and paint from it. Indeed, the high temperature within thefire chamber 61 is enough to single and loosen the paint, oil andgrease, and consume the non-ferrous substances such as sound deadeningmaterial, rubber, upholstery and plastics. Furthermore, the tumblingcreated by the oscillatory motion of the conveying deck 40 tends todislodge the ashes from the scrap metal and most of these ashes becomeentrained in the airstream passing through the fire chamber 61.

Once the scrap reaches the end of the conveying deck 40 the individualpieces thereof are substantially free of contaminants and are physicallyclean from a metallurgical standpoint, but the scrap as a whole will bemixed with some ash. This clean scrap falls onto the removal conveyor 6along with the ashes, and while on the conveyor 6 it is sprayed withwater to cool it and to flush away the dislodged ashes and otherimpurities. The scrap metal thereafter remaining on the conveyor 6 isacceptable for use by steel mills in making new steel.

The gaseous products of combustion and smoke as well as considerable ashin the form of particulates are entrained in the airstream passing overthe conveying deck 40, and after the airstream enters the smokeelimination chamber 102 (FIG. 4) at the discharge end of the oscillatingconveyor 10, its temperature is raised significantly to between l,000F.and I,500F. This elevation in temperature consumes any unburnedsubstances and further eliminates smoke from the air stream.

Thereafter, the airstream enters the cooling chamber 116 (FIG. 4) whereit encounters and flows through the serpentive path between the baffleplates 120, I22 and 124 therein. As the airstream flows along the baffleplates 120, I22 and 124, water from the nozzles 126 is sprayed throughit and this cools the airstream significantly. Indeed, the spray fromthe nozzles 126 supplies enough water to cool the airstream toapproximately 240F. to 260F. Aside from cooling the airstream, the sprayof water from the nozzles 126 impinges against and moistens the baffleplates 120, 122 and 124, and this impingement coupled with the flow ofthe airstream along the baffle plates I20, 122 and 124 removes thelarger particles of material from the airstream. These particulates areflushed out of the cooling chamber 1116 by the spray water whichcascades downwardly across the baffle plates and 122 and is directedinto the scrubber by the drain tube 125. The scrubber 130 in turndischarges the water into the duct 137.

The cooled airstream also enters the slot-type air scrubber I30 (FIGS. 3and 4) where by means of impingemcnt upon wet plates and counterflowwater sprays practically all of the remaining particulates are removedfrom it and its temperature is reduced still further. The spent waterfrom the scrubber 130 joins the water from the cooling chamber 116 andflows downwardly, leaving the scrubber 130 by means of the duct 137. Theairstream is also discharged into the duct 137.

The water stream containing the particulates removed at the coolingchamber 116 and at the scrubber 130 cascades downwardly through the duct137 and flows onto the conical bottom wall 140 of the cyclone collector136 (FIG. 3). Thereafter, it flows to the center of the bottom wall 140where it enters the discharge tube 142 which directs it to the settlingtank 146. The water within the settling tank 146 is relatively quiet andaccordingly the particulates tend to settle to the bottom of the tank146. In this connection, it should be noted that pump 134 draws itswater from the stand pipe 148 which terminates close to the top surfaceof the water within the tank 146 so as to not disturb the settlement ofthe particulates.

The airstream, on the other hand, upon discharging from the duct 137flows tangentially within the cyclone collector 136 and eventually losesvelocity within the collector 136. The loss of velocity causessubstantially all of the remaining particulates to gravitate to thebottom wall 140 and be flushed into the settling tank 146 with the waterstream flowing over that bottom wall,

The airstream after having been freed of the last particulates in thecyclone collector 136 then flows through duct 154 (FIG. I) to the fan156 and is discharged into the atmosphere through the stack I58. Theairstream so discharged, while being thin in oxygen, is for allpractical purposes free of smoke and particulates and accordingly willnot pollute the atmosphere.

This invention is intended to cover all changes and modifications of theexample of the invention herein chosen for purposes of the disclosurewhich do not constitute departures from the spirit and scope of theinvention.

What is claimed is:

l. A high temperature cleaning apparatus for removing surfacecontaminants from metal segments, said apparatus comprising: a conveyorincluding a conveying deck having a receiving end onto whichcontaminanted metal segments are placed and a discharge end, and drivemeans for imparting an oscillatory motion to the conveying deck, theoscillatory motion being such that the metal segments move on theconveying deck from the receiving end to the discharge end, tumbling asthey do .so that different surfaces of the segments are presentedupwardly as the segments move along the deck; closure means extendedover the conveying deck and together with the deck defining a firechamber above the deck, the upwardly presented surface of the deck beingpresented toward and exposed to the fire chamber; burners in the firechamber and positioned such that flames issuing therefrom are directeddownwardly and impinge against the conveying deck and the metal segmentsthereon whereby surface contaminants are burned from the metal segments;ducting connected with the closure means and communicating with the firechamber; and fan means for inducing an airstream in the ducting andthrough the tire chamber so that smoke and particulates resulting fromthe combustion of the contaminants will become entrained in theairstream and will leave the fire chamber through the ducting.

2. The structure according to claim 1 and further characterized byantipollution means for removing smoke and particulates from theairstream; and

wherein the fan. means maintains the airstream within the anti-pollutionmeans. 7

3. The structure according to claim 1 wherein the burners extendtransversely to the direction of flow along the conveying deck andfurther extend substanwherein thesid'es of the closure means arere'moveable, at least in part, to afford access to the conveying deck.

'SfThe structure according to claim 1 wherein the closure meanscomprises a frame, an insulated covering supported on the frame andextending over the conveying deck in upwardly spaced relation thereto soas to form the top of the fire chamber, and side curtains supported bythe frame and defining the sides of the tire chamber, the side curtainsbeing spaced outwardly from the sides of the conveying deck so that aircan be admitted to the fire chamber from the spaces between the sides ofthe conveying deck and the side curtains. 6. The structure-according toclaim wherein at least means for heating the fire chamber; and aconveyor for transporting metal segments through the tire chamber, andsaid conveyor including: a base, a conveying deck supported on the basefor supporting the metal segments, the conveying deck being located inthe closure and exposed to the fire chamber so that the surfacecontaminants will be burned from the metal segments, the conveying deckbeing movable relative to the base and having a receiving end and adischarge end, drive means connected with the conveying deck forimparting oscillatory motion thereto, the oscillatory motion being suchthat the metal segments move along the deck from the receiving end tothe discharge end thereof, tumbling as they do so that differentsurfaces of the segments are presented upwardly, a water pan mounteddirectly below the conveying deck for holding water and also beingoscillated by the drive means, the

water pan being positioned close enough to the conveying deck to enablethe water therein to splash against the underside of the conveying deckas the conveying deck and water pan are oscillated by the drive means,whereby the water in the water pan will cool the conveying deck andprevent it from being distorted.

10. A high temperature cleaning apparatus according to claim 9 whereinthe water pan is mounted rigidly with respect to theconveying deck.

11. A high temperature cleaning apparatus according to claim 9 whereinthe heating means comprises burners which are oriented to direct theflames issuing therefrom downwardly and are positioned close enough tothe conveying deck to enable the flames to impinge against the conveyingdeck and the metal segments thereon.

12. A high temperature cleaning conveyor for removing contaminants frommetal segments, said cleaning conveyor comprising an oscillatingconveyor including a conveying deck having a receiving end onto whichsome of the side curtains'are shiftable inwardly and outwardly relativeto the conveying deck so that the width of the space between theconveying deck and the side curtains can be varied for controlling theamount of air admitted to the fire chamber.

7. The structure according to claim 5 wherein the side curtains areremoveable to expose the fire chamber and to provide access to theconveying deck.

-8. The structure according to claim 1 and further characterized by awaterfilled pan positioned beneath the conveying deck andagitated by thedrive means,

the water-filled pan being close enough to the conveying deck to splashwater upon the underside thereof when agitated whereby the conveyingdeck will not overheat.

9. A high temperature cleaning apparatus for removing surfacecontaminants from metal segments, said apparatus comprising a closuredefining a fire chamber;

the contaminated metal is placed and a discharge end, drive means foragitating the conveying deck to cause it to advance the metal toward thedischarge end, a base, a framework supporting the conveying deck andconnected to the drive means, means supporting the framework on the basesuch that the framework can oscillate relative to the base, a laterallyextending support member carried by the framework and underlying aportion of the conveying deck, a slip pad interposed between andseparating the conveying deck and the laterally extending supportmember, and attaching means having a shank which extends through thelaterally extending support member and the overlying portion of theconveying deck, the overlying portion of the conveying deck having aslot which receives the shank and extends transversely of the directionof advance along the deck, whereby the deck will not buckle whenexpanded by heating; closure means defining a tire cham- .exposed to thefire chamber; and heating means for elevating the temperature of thetire chamber sufficiently to burn contaminants from the metal segmentstmasported on the deck. transported

1. A high temperature cleaning apparatus for removing surfacecontaminants from metal segments, said apparatus comprising: a conveyorincluding a conveying deck having a receiving end onto whichcontaminanted metal segments are placed and a discharge end, and drivemeans for imparting an oscillatory motion to the conveying deck, theoscillatory motion being such that the metal segments move on theconveying deck from the receiving end to the discharge end, tumbling asthey do so that different surfaces of the segments are presentedupwardly as the segments move along the deck; closure means extendedover the conveying deck and together with the deck defining a firechamber above the deck, the upwardly presented surface of the deck beingpresented toward and exposed to the fire chamber; burners in the firechamber and positioned such that flames issuing therefrom are directeddownwardly and impinge against the conveying deck and the metal segmentsthereon whereby surface contaminants are burned from the metal segments;ducting connected with the closure means and communicating with the firechamber; and fan means for inducing an airstream in the ducting andthrough the fire chamber so that smoke and particulates resulting fromthe combustion of the contaminants will become entrained in theairstream and will leave the fire chamber through the ducting.
 2. Thestructure according to claim 1 and further characterized byantipollution means for removing smoke and particulates from theairstream; and wherein the fan means maintains the airstream within theanti-pollution means.
 3. The structure according to claim 1 wherein theburners extend transversely to the direction of flow along the conveyingdeck and further extend substantially from one side of the conveyingdeck to the other.
 4. The structure according to claim 1 wherein theclosure means extends across the top of the conveying deck and alsodownwardly at the sides thereof; and wherein the sides of the closuremeans are removeable, at least in part, to afford access to theconveying deck.
 5. The structure according to claim 1 wherein theclosure means comprises a frame, an insulateD covering supported on theframe and extending over the conveying deck in upwardly spaced relationthereto so as to form the top of the fire chamber, and side curtainssupported by the frame and defining the sides of the fire chamber, theside curtains being spaced outwardly from the sides of the conveyingdeck so that air can be admitted to the fire chamber from the spacesbetween the sides of the conveying deck and the side curtains.
 6. Thestructure according to claim 5 wherein at least some of the sidecurtains are shiftable inwardly and outwardly relative to the conveyingdeck so that the width of the space between the conveying deck and theside curtains can be varied for controlling the amount of air admittedto the fire chamber.
 7. The structure according to claim 5 wherein theside curtains are removeable to expose the fire chamber and to provideaccess to the conveying deck.
 8. The structure according to claim 1 andfurther characterized by a water-filled pan positioned beneath theconveying deck and agitated by the drive means, the water-filled panbeing close enough to the conveying deck to splash water upon theunderside thereof when agitated whereby the conveying deck will notoverheat.
 9. A high temperature cleaning apparatus for removing surfacecontaminants from metal segments, said apparatus comprising a closuredefining a fire chamber; means for heating the fire chamber; and aconveyor for transporting metal segments through the fire chamber, andsaid conveyor including: a base, a conveying deck supported on the basefor supporting the metal segments, the conveying deck being located inthe closure and exposed to the fire chamber so that the surfacecontaminants will be burned from the metal segments, the conveying deckbeing movable relative to the base and having a receiving end and adischarge end, drive means connected with the conveying deck forimparting oscillatory motion thereto, the oscillatory motion being suchthat the metal segments move along the deck from the receiving end tothe discharge end thereof, tumbling as they do so that differentsurfaces of the segments are presented upwardly, a water pan mounteddirectly below the conveying deck for holding water and also beingoscillated by the drive means, the water pan being positioned closeenough to the conveying deck to enable the water therein to splashagainst the underside of the conveying deck as the conveying deck andwater pan are oscillated by the drive means, whereby the water in thewater pan will cool the conveying deck and prevent it from beingdistorted.
 10. A high temperature cleaning apparatus according to claim9 wherein the water pan is mounted rigidly with respect to the conveyingdeck.
 11. A high temperature cleaning apparatus according to claim 9wherein the heating means comprises burners which are oriented to directthe flames issuing therefrom downwardly and are positioned close enoughto the conveying deck to enable the flames to impinge against theconveying deck and the metal segments thereon.
 12. A high temperaturecleaning conveyor for removing contaminants from metal segments, saidcleaning conveyor comprising: an oscillating conveyor including aconveying deck having a receiving end onto which the contaminated metalis placed and a discharge end, drive means for agitating the conveyingdeck to cause it to advance the metal toward the discharge end, a base,a framework supporting the conveying deck and connected to the drivemeans, means supporting the framework on the base such that theframework can oscillate relative to the base, a laterally extendingsupport member carried by the framework and underlying a portion of theconveying deck, a slip pad interposed between and separating theconveying deck and the laterally extending support member, and attachingmeans having a shank which extends through the laterally extendingsupport member and the overlying portion of the conveying deck, theoverlying portion of the conveying deck having a sLot which receives theshank and extends transversely of the direction of advance along thedeck, whereby the deck will not buckle when expanded by heating; closuremeans defining a fire chamber located above the conveying deck andarranged such that the deck and the metal segments thereon are exposedto the fire chamber; and heating means for elevating the temperature ofthe fire chamber sufficiently to burn contaminants from the metalsegments trnasported on the deck. transported